Carrying amount as of the balance sheet date of amounts expected to be recovered under the terms of insurance contracts.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

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Amount of receivable related to a loss contingency accrual. For example, an insurance recovery receivable.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12053-110248

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Commitments and Contingencies (Details) $ in Millions, ₩ in Billions	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2016 KRW (₩)
Hanjin
Loss Contingencies [Line Items]
Anticipated insurance recoveries	$ 4.0
Insurance claims
Loss Contingencies [Line Items]
Estimate of possible loss	18.0
Assessment
Loss Contingencies [Line Items]
Estimate of possible loss		$ 10.4	₩ 11.9
Pre-assessment
Loss Contingencies [Line Items]
Estimate of possible loss		$ 17.6	₩ 20.1
Collectibility of receivables \| Hanjin
Loss Contingencies [Line Items]
Loss contingency, outstanding receivable	$ 4.0